1. Field
One or more embodiments of the present invention relate to a rechargeable battery. More particularly, one or more embodiments of the present invention relate to a rechargeable battery with a safety device having an improved structure.
2. Description of the Related Art
A rechargeable battery is a battery that can be charged and discharged, which is different from a primary battery, which is not rechargeable. A rechargeable battery with low capacity can be used for small portable electronic devices such as mobile phones, laptop computers, and camcorders. On the other hand, a rechargeable battery with high capacity can be used as a power source for driving a motor of a hybrid electric automobile and the like, or as a large-capacity power storage device.
A high power rechargeable battery using a non-aqueous electrolyte of high energy density has been recently developed. A plurality of these rechargeable batteries can be coupled in series to form a large capacity battery module so that the high power rechargeable battery may be used to drive a device requiring high power (e.g., a motor in an electric vehicle). The rechargeable battery can be formed in a cylindrical or rectangular shape.
If a conductive foreign object, such as a nail or a screw, enters the rechargeable battery from the outside, a short circuit may occur in the rechargeable battery. In the event of a short circuit, the internal temperature of the rechargeable battery may sharply rise and the rechargeable battery may ignite or explode.
Moreover, a positive or negative electrode uncoated portion of the rechargeable battery is generally made of a very thin sheet metal, and this may cause the positive or negative electrode uncoated portion to be torn or to stick to a current collecting tab during the process of welding the current collecting tab having a large thickness (or a thick current collecting tab) to the positive or negative electrode uncoated portion.
The above information disclosed in this Background section is only for enhancement of understanding of the background of the invention and therefore it may contain information that does not form the prior art that is already known in this country to a person of ordinary skill in the art.